Hydraulic sorting apparatus

ABSTRACT

The particulate-sorting apparatus herein comprises a flume sloping at a shallow angle and containing a free-surface flow of liquid at a given rate and being provided with means for generating vibratory motion on the flume along an axis at an acute angle to the flow and contained in a vertical plane passing through the flow axis.

United States Patent [72] Inventor Elie Condollos Grenoble, France [21 Appl. No. 787,088

[22] Filed Dec. 26, 1968 [45] Patented Aug. 17, 1971 [73] Assignee Soclete Grenobloise d'Etudes et dApplicatlons Grenoble, France [32] Priority Dec. 28, 1967 [33] France [$4] HYDRAULIC SORTING APPARATUS 5 Claims, 9 Drawing Figs.

[52] US. Cl 209/157, 209/442 [51] InLCl B03|J 3/12 [50] Field 01 Search 209/156,

[ Relerences Cited UNITED STATES PATENTS 2,079,059 5/1937 Winkleman 209/481 X 2,660,305 11/1953 Labouygues 209/157 X 2,832,472 4/1958 Pierce 209/442 2,946,438 7/1960 Belugou et al7 209/156 2,995,244 8/1961 Schlicksupp 209/472 X 3,441 ,135 4/1969 Lapple 209/144 FOREIGN PATENTS 712,148 7/1954 Great Britain 209/481 499,998 2/l939 Great Britain 209/437 Primary Examiner- Frank W. Lutter Assistant Examiner- Ralph J. Hill Attorneys-Sylvester J. Liddy, John J. Han, Joe E. Daniels and Charles E. Baxley ABSTRACT: The particulate-sorting apparatus herein comprises a flame sloping at a shallow angle and containing a freesurface flow of liquid at a given rate and being provided with means for generating vibratory motion on the flume along an axis at an acute angle to the flow and contained in a vertical plane passing through the flow axis.

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PATENIEU AUG] 7 nan 3, 599 791 sum 2 [1F 2 51. IE CONDOL /05 B Y i Ar-roamsr HYDRAULIC SORTING APPARATUS THE INVENTION The present invention is concerned with a sorting apparatus for granular material which makes use of a free-surface hydraulic flow in the performance of the sorting operation.

It is known that when a flow of the indicated type conveys materials of different densities at a given rate of liquid flow, the least dense materials will be picked up and conveyed very rapidly by the flow, while the densest materials will settle out at the bottom and move along much more slowly than the least dense materials. It has been found however, that if there is imparted to the wall of the conduit constituting the bed underneath a flow of this type, an appropriate movement such as to cause the wall to have a vibratory acceleration higher than the acceleration of gravity, segregation of the materials is facilitated, and the materials settled out on the wall or bed underneath the flow are caused to move against the flow while the remaining materials are conveyed downstream by the flow.

In accordance with the invention, the aforesaid phenomenon is created by imparting vibrations to the bed wall along the axis which is disposed at an acute angle to the flow and contained in a vertical plane passing through the flow axis. In analyzing all of the various phenomena which contribute toward the separation of dense from light particles when a flume bottom is vibrated in the manner aforesaid, it has been found that the considerable mechanical effect of a vibration capable of facilitating segregation of the materials settled out on the flume bottom, superimposes itself on the geometrical and hydraulic flow conditions. The force components of such vibration on the particles in the layer of materials settled out on the flume bottom, accelerate the progress of the dense materials and especially the finest particles thereof, towards the bottom of the layer, while causing any light particles that settled out with the dense particles, to rise up into the upper part of the layer. The dense particles in the layer will move upstream in small bounds, while the light particles are carried downstream with the flow.

The features in a sorting apparatus embodying the invention and capable of producing the above described phenomenon, include 1. A flume of definite geometrical characteristics, especially as regards width and slope, in which a free-surface liquid flow takes place at a certain rate.

2. The materials to be sorted are fed in about halfway along the length of the flume, i.e., into the central portion thereof.

3. The flume is provided with means for imparting the appropriate vibratory motion to the bottom wall thereof.

4. The liquid for the free-surface flow is fed in by a device so disposed on the upstream part of the flume at a certain distance from its end that substantially all the liquid fed into the flume flows from upstream to downstream.

5. A certain quantity of water may be fed in with the materials to be sorted to activate the separation process.

It will be understood from the foregoing, that if the rate of flow in the flume is appropriately adjusted to ensure rapid conveyance of the least dense materials by the flow and the settling particles out of the densest materials on the flow bottom, the least dense particles will be carried away by the flow to emerge at the downstream end of the flume, and the densest materials, after settling out on the flume bottom, are conveyed upstream by the flume bottom movements and emerge at the upstream end of the flume beyond the point at which the liquid is fed in. The hydraulic laws governing the conveyance of solids in free-surface channel flow show that, for materials of given density, there is a definite relationship between the formation of a deposit on the bottom of a flume, the concentration of the material in the liquid, the grain size of the material, and the flume slope. The greater the grain size of the material, the steeper the flume bottom slope has to be to prevent deposit formation. This relationship therefore, shows that the flume slope is of considerable importance, and that it must be determined in terms of the physical properties of the materials to be separated out. Further, choice of the right slope must ensure that the light materials can be conveyed at maximum concentration in order that the maximum possible solid throughput per flume can be achieved.

Since the hydraulic conditions for free-surface flow in a sin gle or unit flume are determined by the principle variables referred to above, i.e., physical properties of the materials, concentrations, flume slope, depth of flow, and water discharge per unit width, it is necessary to determine the unit width in order to achieve stable flow. The unit flume width should not exceed a certain value, otherwise the flow will be unstable and wander" over the full width of the flurne with a consequent varying depth of water across the flume, unstable deposit formation, and poor, or greatly impaired separation. Stable operation can be attained in a wide flume by partitioning into several unit" flumes of a width that will ensure a sta hie hydraulic flow with materials in each one of them. Unit flumes of varying width along their lengths can also be used in special cases where it is desired to vary the depth of water in the flume so as to modify its sorting equation. For most of the materials which can be separated with apparatus of this type, the unit flume can be rectangular in cross section. In special cases, however, as where greater lateral flow stability is required, the flume bottom can be made more or less triangular or concave. In certain ore separation applications, the flume can be made fluted, with triangular or concave grooves along its length.

For a better understanding of the invention, reference is made to the following explanation of several nonlimitive examples of practical forms of the invention and which should be read in connection with the accompanying drawings, in which FIG. 1 is a diagrammatic longitudinal section of a sorting apparatus embodying the invention;

FIG. 2 is a diagrammatic longitudinal section looking along the line lI-Il of the embodiment shown in FIG. 3 of the drawings;

FIG. 3 is a cross section looking along the line 3-3 of FIG. 2;

FIG. 4 is a longitudinal section of an apparatus designed to sort three different materials;

FIG. 5 is a diagrammatic view of another form of the invention;

FIG. 6 is a top plan view of a unit flume of varying width along its length;

FIG. 7 is a sectional view ofa unit flume with a concave bottom;

FIG. 8 is a sectional view ofa unit flume with a substantially triangularly shaped bottom; and

FIG. 9 is a sectional view of a unit flume with triangular and concave grooves along the bottom thereof.

In FIG. 1 of the drawings, the numeral 10 generally designates a flume through which a liquid ll flows with a free surface at a certain rate in the direction of the arrow f. The flume 10 is inclined at a slight slope angle so that the liquid 11 flows down in the direction of the slope. For most common sorting applications, e.g. the sorting of heavy ore from beach sand, the angle that the flume is inclined with respect to the horizontal is smaller than about 15. As previously indicated, the given rate of flow of the liquid through the flume is a function of the slope, and also of the grain size and density of the material that is to be processed.

The materials 12 to be sorted are fed into the flow of liquid 1! through an inlet 14 located approximately halfway along the length of the flume, i.e., in the central portion of the flume. The materials to be sorted may be introduced into the flume in either a dry condition or with a given quantity of water. The water 11 required for the hydraulic flow in the flume is fed in through an inlet 13 located at such given distance from the upstream or upper end 15 of the flume that substantially all the flow runs from such upstream end to the downstream or lower end 16 ofthe flume.

The bottom or bed wall of the flume 10 in the embodiment of FIG. 1 has connected thereto a device 17 for imparting vibratory motion to such wall in such a way that the materials settled out on the flume bottom are made to move upstream and emerge at the flume end 15. The device 17 may be any suitable vibrator known to the art, such as a known standard electro magnetic vibrator capable of operating at the available line frequency and having a stroke of about 1.2 millimeters. The frequency of vibration may range from about l-] l0 cycles per second. It has been found that if the frequency of vibration is too high or too low, the apparatus does not operate correctly and the segregation of materials and the bed movement will be deficient. The device 17 is mounted on the bottom flume wall to generate vibration at an acute angle a with respect to the flume bottom and in the vertical plane containing the flume centerline of flow axis. The direction of vibration is indicated in FIG. 1 of the drawings by the axis or line 18-18 and the immergent angle a which such line 18-18 makes with either the flume bottom, the flume centerline, the flow, or the flow axis, may be called in this specification and the appended claims, a negative acute angle, or ain FIG. 1, whereas the emergent angle a which such line makes with the aforesaid or the top longitudinal edges of the flume as shown in FIG. 1, may be called a positive acute angle, or 0+. It might be said more specifically therefore that the vibrations are directed by the device 17 along an axis or line disposed in a vertical plane containing the axis of liquid flow, or the flume centerline, and at a positive acute angle to such flow axis or centerline upstream from its point of intersection with the latter. The angle a is preferably between about 40 and 50".

It will be understood from the foregoing, that in the practice of the invention the rate of flow of the liquid 11 in the direction of the arrow f is set to ensure rapid entrainment by such flow of the least dense particles in the material 12 being sorted and to make the densest particles in the material 12 settle out on the bottom of the flume. Thus a large part of the least dense particles will be carried away immediately by the flow towards the downstream end 16 of the flume, and the remainder thereof which are entrapped among the densest particles, will settle out with the latter a short distance downstream from the material feed inlet 14. The particles settling out will form a deposit or mound 19 in the flume. The acceleration or vibratory motion applied to the bottom wall of the flume by the device 17 is etfective to cause the wall to move equally in both directions along the line 18-18 throughout its length to free the light particles from the mound 19 and to cause the heavy particles to move in successive bounds along the bottom walls of the flume. The freed light particles will rise to the surface of the deposit or mound 19 where the flow of water picks them up and carries them downstream to the lower discharge end 16 of the flume. The heavier particles are extracted at the upstream end of the flume.

In the embodiment of the invention illustrated in FIGS. 2 and 3 of the drawings, there is shown a flume 20 which is too wide for stable flow. As shown, stable operation is attained by dividing the flume 20 into several unit flumes 21 by partitions 22 extending along its full length. Mounted on the sidewalls of the flume 20 is a frame 23 carrying an electromagnetic vibrator 24. The frame 23 transmits the vibrations applied thereto by the vibrator to the sidewalls ol' the flume 20 and through the latter to the flume bottom 25. As in the case of the vibrator 17, the vibratory motion generated by the vibrator 24 is applied to the bottom 25 of the flume 20 at an acute angle to the flow in a plane vertical to the flow axis.

The material to be sorted in the apparatus in FIGS. 2 and 3 is fed into a rotary distributor 28 which does not vibrate and which is rotated continuously in the direction of the arrow by a motor 29. In its rotary movement, the distributor 28 feeds equal quantities of the material feeding down a chute 30 into six circularly arranged hoppers 31 connected by flexible pipes 32 to six individual distributors 33 located centrally on the six unit flumes 21. The individual distributors 33 are constructed in a known manner so that each maintains a continuous feed of material to its associated unit flume 21 from the discontinuous supply thereof that it receives from the rotary distributor 28, and distributes such continuous feed of material evenly over the width of its associated unit flume. As in the embodiment of FIG. 1, a certain quantity of water may also be fed in with the material, as by supplying it to the distributor 28.

The sorting flow of water is fed into a constant-level tank 35 of known construction and distributed from the latter to the six unit flumes 21 by six pipes 36 and six distributors 37. Equal rates of flow to the unit flumes are controlled by valves 38 in the pipes 36. The individual distributors 37 are arranged with respect to the unit flumes 21 in the same manner as in the inlet 13 with respect to the flume 10 in the embodiment of FIG. 1.

It will be understood from the explanation previously given with respect to the embodiment of FIG. 1, that in the operation of the apparatus of FIGS. 2 and 3, the material delivered for sorting at each unit flume 21 is separated by the flow. The light particles fed into each unit flume are conveyed downstream by the flows in such units and discharged with the water at the lower end 39 of the flume 20. The dense particles settle out into a deposit 40 on the bottom of each unit flume 21 and are made to move upstream against the flow by the vibration generated on the flume bottom 25 by the vibrator 24. That portion of the light particles which become trapped with the dense particles in the settling out process, under the vibrating motion imparted to the flume bottom 25 rise to the top of the deposits 40 in the unit flumes 21 where they are picked up by the flows and washed away downstream to the lower discharge end 39 of the flume. The concentrated dense particles emerge from the hydraulic flow level with the water distributors and come out partly dry (drip-dry") at the upstream flume end 41.

The type of apparatus depicted in FIGS. 1-3 has been used to separate several materials of different densities; for example, heavy ore such as ilmenite (S.G.=4.2) from beach sand (S.G.=2.65. This particular sand was mostly quartz with grain sizes ranging from microns to 2 mms., while the ilmenite particles ranged from 80 microns to 0.5 mms. The bulk ore before sorting contained 8 percent heavy materials and 92 percent sand.

In sorting this sand there was used an apparatus having a flume divided into nine unit flumes each of 93 millimeters in width. The flume angle of slope was 7 and the incident vibration angle a was 45. Vibration frequency and amplitude were 50 cycles per second and 1.2 millimeters, respectively. The rate of feed of the sand to the flume was 5.20 tons per hour and the rate of feed of the water was 4.3 cubic meters of water per hour. This distance of the water inlets or distributors from the upstream end of the flume was 20 centimeters. The rate of flow of the water in the flume was 60 centimeters per second. With the apparatus operating under these conditions, it yielded the following:

1. Practically pure sand, i.e., 89 percent of the material fed 2. Nearly all the ilmenite mixed with a small percentage of sand.

It has been found that in certain cases of dil'licult processing, it is advisable to separate two ore more materials by means of several flumes arranged in series. FIG. 4 of the drawings illustrates an apparatus which has been designed for the separation of three materials, i.e., a dense material, a light material, and a material of intermediate density. In the apparatus shown in FIG. 4, the two sloping flumes 45 and 46 in series are arranged so that the materials discharging from the upstream end 47 of the flume 45 fall into the central portion of the flume 46. Associated with the two flumes 45 and 46 is a frame 48 for supporting the vibrator 49 and for transmitting the vibratory motion created thereby to the bottom walls of the two flumes. The mixture of materials to be separated is fed into flume 45 by the distributor 50 and the washing flow of water for such flume is fed in by the distributor 51. The flow of water from the distributor 51 carries the lightest materials in the mixture to the downstream end 52 of the flume 45 from whence they are discharged with the water. The dense and intermediate materials in the feed mixture come out at the upstream end 47 of the flume and fall into flume 46. A second liquid distributor 53 provides the washing flow of water for the flume 46. The flow in flume 46 carries the intermediate material with it to the downstream end 54 of such flume; the dense material in the mixture coming out at the upstream end 55 of the flume 46. The slopes and rates of water flow for the two flumes 45, 46 are chosen as appropriate for the densities and quantities of material passing through each flume.

An arrangement of flumes in the manner of the flumes 45 and 46 in FIG. 4 can also be used with three or even four flumes mounted in series on a common frame and with a com mon distributor. In certain cases of separation of two ores. where it is the intention to obtain each ore in the purest possible state, it may be advisable to use the arrangement shown in FIG. 5 of the drawings. The arrangement of flumes in FIG. 5 is similar to that shown in FIG. 4 and accordingly the parts depicted in FIG. 5 which are similar to those shown in FIG. 4 have been given the same reference numerals. The apparatus of FIG. 5 differs from that of FIG. 4, in that the rate of flow in flume 45 has been approximately adjusted to obtain a pure light material at the downstream end 52 of such flume. All of the dense materials with a small quantity of the light material come out at the upstream end 47 of the flume 45 and fall into the second flume 46 for further sorting. The flow in flume 46 is adjusted so that a practically pure dense material is delivered at its upstream end 55, and the light materials with a small percentage of dense material at its downstream end 54. The materials discharging from the downstream end 54 of the flume 46 are sent back to the material distributor 50 associated with the first flume 45 for further sorting with the fresh bulk ore being fed to such distributor for sorting.

FIG. 6 of the drawings shows for purposes of illustration one manner in which a flume or flume subchannels or units may be varied in width along the flume length to vary the depth of water in the flume and hence modify its sorting operation.

FIGS. 7 and 8 show flumes with concave and triangular bottoms, respectively, for establishing a greater lateral flow stability in the flumes.

The flume shown in F IG. 9 of the drawings, is provided with a bottom wall 56 whose flow supporting surface is fluted. As indicated in such figure, the longitudinally extending grooves in such flume bottom may be triangularly shaped grooves 57. or concave grooves 58, or both.

While there has been hereinabove described and illustrated in the drawings preferred embodiments of the invention, it will be understood that variants thereof may be made without departing from the spirit of the invention, or the scope of the appended claims.

1 claim:

1. Apparatus for sorting solid particulate material utilizinp a free-surface hydraulic flow, comprising a flume having a downstream liquid outlet and an upstream solid material outlet and sloping downwardly at a given shallow angle to the horizon toward said downstream liquid outlet, upstream means for providing a free-surface downhill flow of liquid free-surface a given rate in said flume, means downstream from said upstream means for feeding the solid particulate material to be sorted into the liquid flow, the given rate of free-surface flow of the liquid at such given angle of flow being such that substantially all of the liquid and the solid particles entrained in the angularly disposed free-surface flow thereof discharge through said downstream outlet and the denser particles of such solid material settle out into a deposit on the bottom of said flume, and means for generating vibratory motion on the flume along an axis in a vertical plane passing through the flow axis and disposed at such acute angle to the angularly disposed flow that the denser particles are made to move uphill against the downhill flow and lighter particles entrapped by the settled denser particles are freed from the latter and picked up by the flow.

2. Apparatus as defined in claim I. in which said flume has a slogie of less than about l5.

. Apparatus as defined in claim I, in which said vibratory means is constructed and arranged to generate vibratory mo tion along an axis disposed at a given positive acute angle to the flow axis upstream from its point of intersection with the latter.

4. Apparatus as defined in claim 1, in which said acute angle is between about 40 and 50.

5. The method of sorting solid particulate material, which comprises introducing such solid material into a free-surface hydraulic flow in a conduit having a downstream liquid outlet and an upstream solid material outlet and sloping downwardly at a given shallow angle toward the downstream liquid outlet, regulating the downhill flow of the free-surface liquid at such given rate that the light solid particles are entrained in the flow and the denser solid particles settle out into a deposit on the bottom of the conduit, and generating vibratory motion on the floor of the conduit along an axis in a vertical plane passing through the flow axis and disposed at such acute angle to the angularly disposed flow that the denser solid particles are made to move uphill against the downhill flow and lighter particles entrapped by the settled denser particles are freed from the latter and picked up by the flow.

PMOBO UNITED STA'I.ES PAIENT OFFICE 56 CERTIFICATE OF (IORRECTION Patent No. 3599.791 Dated august 17, 1971 Inventor(s) Elie Condolios It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Col. 1 line 63, after "settling" --particles-- should be deleted.

Col. 3 ling ig, after "bounds" --upstrea.m-- should be inseried,

'Col. 3 lineifi, "wells" should be --wa.ll--.

Col. 3 line "F0, "movement" should be --movements--. Col. 4 line 37, after "2.65" should be inserted.

Col. 6 line 10, "free-surface" should be deleted and before "a" --at-- should be inserted.

Signed and sealed this 28th day of March 1972.

SEAL) :test:

)WARD M.F'LETCHER, JR. ROBERT GOTTSCHALK :testing Officer Commissioner of Patents 

1. Apparatus for sorting solid particulate material utilizing a free-surface hydraulic flow, comprising a flume having a downstream liquid outlet and an upstream solid material outlet and sloping downwardly at a given shallow angle to the horizon toward said downstream liquid outlet, upstream means for providing a free-surface downhill flow of liquid free-surface a given rate in said flume, means downstream from said upstream means for feeding the solid particulate material to be sorted into the liquid flow, the given rate of free-surface flow of the liquid at such given angle of flow being such that substantially all of the liquid and the solid particles entrained in the angularly disposed free-surface flow thereof discharge through said downstream outlet and the denser particles of such solid material settle out into a deposit on the bottom of said flume, and means for generating vibratory motion on the flume along an axis in a vertical plane passing through the flow axis and disposed at such acute angle to the angularly disposed flow that the denser particles are made to move uphill against the downhill flow and lighter particles entrapped by the settled denser particles are freed from the latter and picked up by the flow.
 2. Apparatus as defined in claim 1, in which said flume has a slope of less than about 15*.
 3. Apparatus as defined in claim 1, in which said vibratory means is constructed and arranged to generate vibratory motion along an axis disposed at a given positive acute angle to the flow axis upstream from its point of intersection with the latter.
 4. Apparatus as defined in claim 1, in which said acute angle is between about 40* and 50*.
 5. The method of sorting solid particulate material, which comprises introducing such solid material into a free-surface hydraulic flow in a conduit having a downstream liquid outlet and an upstream solid material outlet and sloping downwardly at a given shallow angle toward the downstream liquid outlet, regulating the downhill flow of the free-surface liquid at such given rate that the light solid particles are entrained in the flow and the denser solid particles settle out into a deposit on the bottom of the conduit, and generating vibratory motion on the floor of the conduit along an axis in a vertical plane passing through the flow axis and disposed at such acute angle to the angularly disposed flow that the denser solid particles are made to move uphill against the downhill flow and lighter particles entrapped by the settled denser particles are freed from the latter and picked up by the flow. 